handle native objects in StringFormatter, minor fixes

Author: lukasstadler

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/PythonLanguage.java

@@ -51,7 +51,6 @@
 import com.oracle.graal.python.builtins.objects.type.PythonClass;
 import com.oracle.graal.python.nodes.BuiltinNames;
 import com.oracle.graal.python.nodes.NodeFactory;
-import com.oracle.graal.python.nodes.PNode;
 import com.oracle.graal.python.nodes.call.InvokeNode;
 import com.oracle.graal.python.nodes.control.TopLevelExceptionHandler;
 import com.oracle.graal.python.nodes.expression.ExpressionNode;
@@ -306,7 +305,7 @@ protected static ExpressionNode parseInline(Source code, PythonContext context,
 
     @Override
     protected boolean isObjectOfLanguage(Object object) {
-        return object instanceof PNode || object instanceof PythonObject;
+        return object instanceof PythonAbstractObject;
     }
 
     @Override

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/formatting/StringFormatter.java

@@ -17,6 +17,7 @@
 import java.util.function.BiFunction;
 
 import com.oracle.graal.python.builtins.objects.PNone;
+import com.oracle.graal.python.builtins.objects.PythonAbstractObject;
 import com.oracle.graal.python.builtins.objects.bytes.PBytes;
 import com.oracle.graal.python.builtins.objects.dict.PDict;
 import com.oracle.graal.python.builtins.objects.function.PArguments;
@@ -120,7 +121,7 @@ private static Object asNumber(Object arg, CallDispatchNode callNode, BiFunction
         } else if (arg instanceof Double) {
             // A common case where it is safe to return arg.__int__()
             return ((Double) arg).intValue();
-        } else if (arg instanceof PythonObject) {
+        } else if (arg instanceof PythonAbstractObject) {
             // Try again with arg.__int__()
             try {
                 // Result is the result of arg.__int__() if that works
@@ -345,7 +346,7 @@ public Object format(Object args1, CallDispatchNode callNode, BiFunction<Object,
                         ft.format(((PString) arg).toString());
                     } else if (arg instanceof PBytes) {
                         ft.format(((PBytes) arg).toString());
-                    } else if (arg instanceof PythonObject && ((bytesAttribute = lookupAttribute.apply(arg, __BYTES__)) != PNone.NO_VALUE)) {
+                    } else if (arg instanceof PythonAbstractObject && ((bytesAttribute = lookupAttribute.apply(arg, __BYTES__)) != PNone.NO_VALUE)) {
                         Object result = callNode.executeCall(null, bytesAttribute, createArgs(arg), PKeyword.EMPTY_KEYWORDS);
                         ft.format(result.toString());
                     } else {